<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>盒子模型内边距</title>
    <style>
        .c1{
            width: 200px;
            height: 100px;
            background-color: red;
            /*padding-left: 100px;*/
            /*padding-top: 100px;*/
            padding: 100px;
        }
        .c2{
            width: 200px;
            height: 100px;
            background-color: green;
        }
    </style>
</head>
<body>
<div class="c1">这是一个div</div>
<div class="c2"></div>
</body>
</html>